Conventionally, one time programmable ROMs (OTP) to which data is programmable only one time are known as a programmable ROM. As an example of the OTPs, a semiconductor memory in which a threshold of a field effect transistor that configures a static RAM (SRAM) is varied by negative bias threshold instability (NBTI), and data is programmed with the variation is known.
In such a semiconductor memory, there is a failure due to programming of data using the NBTI, such as a stochastic failure of the programming.